261278510863 has 8 divisors (see below), whose sum is σ = 263240364240. Its totient is φ = 259317831360.

The previous prime is 261278510851. The next prime is 261278510869. The reversal of 261278510863 is 368015872162.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261278510863 - 2⁹ = 261278510351 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261278510869) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155931 + ... + 739507.

It is an arithmetic number, because the mean of its divisors is an integer number (32905045530).

Almost surely, 2^261278510863 is an apocalyptic number.

261278510863 is a deficient number, since it is larger than the sum of its proper divisors (1961853377).

261278510863 is a wasteful number, since it uses less digits than its factorization.

261278510863 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 586937.

The product of its (nonzero) digits is 967680, while the sum is 49.

The spelling of 261278510863 in words is "two hundred sixty-one billion, two hundred seventy-eight million, five hundred ten thousand, eight hundred sixty-three".